Level-controlling device for containers of liquid



0. ECKERLE ETAL Aug. 29, 1967 LEVEL-CONTROLLING DEVICE FOR CONTAINERS OFLIQUID 4 Sheets-Sheet 1 Filed Feb. 11, 1965 Hlllllll FIG. I

INVENTORS:

OTTO ECKERLE and HELMUT VVEINZIE RL. M

TO NEY;

g- 29, 1967 o. ECKERLE ETAL 3,339,042

LEVEL-CONTROLLING DEVICE FOR CONTAINERS OF LIQUID Filed Feb. 11, 1965 4Sheets-Sheet 2 INVENTORS:

OTTO ECKERLE and HELMUT WEINZIERL.

ATTORNE Y 1967 o. ECKERLE ETAL 3,339,042

LEVEL-CONTROLLING DEVICE FOR CONTAINERS OF LIQUID Filed Feb. 11, 1965 4Sheets-Sheet 3 FIG. 3

INVENTORS:

OTTO ECIGERLE and HELMUT WEINZIERL.

ATTORNEY.

1967 o. ECKERLE ETAL 3,339,042

LEVEL-CONTROLLING DEVICE FOR CONTAINER S OF LIQUID Filed Feb. 11, 1965 4sheets-sheet 4 INVENTORS:

OTTO ECKERLE and HELMUT WEINZIERL.

A TTORNE Y.

United States Patent 3,339,042 LEVEL-CONTROLLING DEVICE FOR CONTAINERS0F LIQUID Otto Eckerle, Am Bergwald 3, Malsch, Germany, and HelmutWeinzierl, Rastatt, Germany; said Weinzierl assignor to said EckerleFiled Feb. 11, 1965, Ser. No. 431,900 2 Claims. (Cl. 200-84) The'present invention deals with a level-controlling device for reservoirsor tanks designed to turn a feed pump on and off by means of an electricspring contact switch, mechanically actuated by means of a float.

In the conventional devices of the prior art, disturbances andvariations in setting the switches are caused to a large extent as aresult of jolts or in the process of assembly, repairs and inspectionthereof to a degree often so considerable that the operation of theswitch is interrupted.

It is the primary object of the present invention to provide a device inwhich the accuracy of the settings is unaffected by temperaturevariations, Vibrations, by the assembly of the device and inspectionsthereof.

Another object of the invention is to eliminate these inaccuracies byproviding a holder or support member made of one piece and mounting thefloat bearing and the switch with the switch tongue thereon. Because ofthis provision, normally detrimental influences of the type describedabove cannot change the setting of the device because the two essentialelements, i.e. the float bearing and the switch tongue bearing, aredisposed on the same body so that a mutual displacement thereof becomesimpossible.

Still another object of the invention is to provide the holder orsupport member with a fastening plate tightly screwed onto the openingof a terminal or connection box, preferably made of plastic whichaccommodates the elements most susceptible to disturbances. Since theseelements are usually the switch contacts as well as the electricconnection, the fastening plate is suitably disposed between the floatbearing and the switch. In such an instance, the plate is provided withopenings through which extend tongue-actuating members controlled by thefloat arm.

Other objects and advantages of the invention are taught by thefollowing description which describes a preferred embodiment thereof indetail in connection with the accompanying drawings, wherein FIGURE 1shows a top plan view of a level-controlling device according to thepresent invention;

FIGURE 2 is a vertical cross-sectional view taken along line II-II ofFIGURE 1;

FIGURE 3 is a vertical cross-sectional view taken along line III-III ofFIGURE 1, and

FIGURE 4 illustrates schematically the actuation of the switch tongue indifferent positions of the float.

In the drawings wherein like reference numerals describe the same orequivalent structures it will become apparent to those skilled in theart, particularly from FIGURES 2 and 3, that the bearing of the floatarm 11 as well as the switch lever 12 and the switch 13 operated by itare carried by a common holder or support member 14. The latter hasbetween the switch lever 12 and the float bearing 10 a fastening plate15 which is screwed in a sealing manner onto the opening 17 of aterminal or connection box 18 by means of screws 16. This box ispreferably made of plastic. The switch lever 12 which is protectivelyreceived by or accommodated in the connection box is pivotally held atthe holder or support member about an axis 20 parallel to the axis ofrotation of the float. The switch lever acts upon the switch 13 by meansof an adjusting screw 21. The actuation or 3,339,042 Patented Aug. 29,1967 float bearing. Rod 22 is in an operative engagement with the switchlever when the float 6 is lowered downwardly from the horizontalposition 24 thereof (FIG. 4). The other control rod 23 is in engagementwith the switch lever when the float is raised above the horizontalposition so that the switch lever,12 will actuate the switch 13 off andon whenever the operating range is exceeded either upwardly ordownwardly.

A third rod 30 is disposed adjacent the holder or support member 14 andextends between the control rods 22 and 23 through a bore in thefastening plate to the switch lever. The rod 30 rests with the other endthereof and with the interposition of an adjusting screw 31 on the freeend of a bent bimetal 32 which actuates the rod and is secured to theholder or support member.

The holder or support member 14 with a bearing surface 33 thereof alsoserves as an abutment for the pretensioned spring 9 of a trip rod 34which raises the float into its horizontal position, acts on the end ofthe float arm 11 facing away from the float and is connected with atripping pin or plunger 7 by means of a spring 8.

Due to the fact that all the essential control elements are disposed andguided at the same holder or support member, mutual displacements duringthe assembly, during an inspection or because of vibrations are avoidedand the accuracy of the setting is not affected.

In order to achieve a simple connection between the float 6 and thefloat arm 11, the latter is provided with a bent hook 35 which receivesthe float with a snapping effect and which expediently comprises a beador stifTening corrugation 37 enclosing the sealing reinforcement 36 ofthe float and preventing the axial displacement of the latter.

In operation, the float rests in the liquid in a reservoir or tank, andthe bimetallic strip 32 is subme-rsed in the liquid.

Referring to FIG. 4, four positions for the float 6 are shown. The pumpis energized only when the float 6 is between an upper and lowerintermediate position such as the two middle positions in FIG. 4. If theliquid level in the reservoir rises above the upper intermediate leveland the float 6 rises to the uppermost position shown, the pump isturned off. As the float rises and the float arm 11 pivots about bearing10 in a counter-clockwise direction, actuating rod 23 is pressed againstthe switch lever 12, opening the switch contacts and de-energizing thepump. As the float 6 falls, the actuating rod 23 is lowered, and theswitch contacts close, energizing the pump.

If the liquid level were to fall below the lower intermediate level tothe lowermost position shown in FIG. 4, actuating control rod 22 wouldsimilarly be pressed upward against the switch lever 12, opening theswitch contacts, and de-energizing the pump. To start the pump again, itis necessary to lift the float 6 using button 7 and rod 34, pressing thebutton until the float 6 is raised to an intermediate position and thepump is energized.

In normal operation, oil or liquid is always intended to be present inthe reservoir, and the float 6 is maintained at an intermediateposition. Only when some disturbance or mechanical malfuntion occursdoes the liquid level in the system fall below the lower intermediateposition. Thus it is solely a safety measure to prevent pump operationduring the disturbance.

Similarly the bimetal strip 32 is a safety device. With some liquidsystems, particularly oil feeding systems, it is desirable to turn thepump off if the liquid in the systern risse above a certain temperature.The bimetallic strip 32 actuates rod 30, pressing it against the switchlever 12 and de-energizing the pump when the temperature has risen abovea certain level.

While we have disclosed the form of mechanism presently preferred by usfor carrying the invention into practice, numerous modifications,alterations and substitutions of equivalents will occur to those skilledin the art, after a study of the foregoing specification. Hence thedisclosure should be taken in an illustrative rather than a limitingsense; and it is our desire and intention to reserve all modificationsand substitutions of equivalents within the scope of the subjoinedclaims.

Having now fully disclosed the invention, what we claim and desire tosecure by Letters Patent is:

1. A switch device for making and breaking an electric circuit as afunction of properties of liquid in a container, comprising: a one-piecesupport; a float arm mounted on said support pivotably about a floatpivot axis; a float attached to said float arm away from said floatpivot axis; a switch arm mounted on said support pivotably about aswitch arm pivot axis; said switch arm pivot axis being removed fromsaid float pivot axis; said float pivot axis being substantiallyparallel to said switch arm pivot axis; two rods, one pivotablyconnected to the float arm on one side of the float pivot axis, onepivotably connected to the float arm on the other side of the floatpivot axis; both rods abutting on said switch arm in a sliding pushingcontact on the same side of said switch arm pivot axis when said switcharm is in its circuit making position, a guide means forming an integralpart of said one-piece support to prevent lateral vibration anddeflection of said rod means; said guide means being a plate having aguide hole for each rod; said plate located between said float arm andsaid switch arm; each rod passing through its respective hole; saidholes providing lateral support to said rods; and a make-break switchmeans operated by the movement of said switch arm.

2. A switch device as claimed in claim 1, further comprising a third rodextending through a guide hole in said plate and abutable on said switcharm on said same side and a bimetallic strip connected at one end tosaid support at a submerging position, connected at its other end tosaid third rod and deflectable according to temperature changein theaxial direction of said third rod.

References Cited UNITED STATES PATENTS BERNARD A. GILHEANY, PrimaryExaminer.

H. A. LEWITTER, Assistant Examiner.

1. A SWITCH DEVICE FOR MAKING AND BREAKING AN ELECTRIC CIRCUIT AS AFUNCTION OF PROPERTIES OF LIQUID IN A CONTAINER, COMPRISING: A ONE-PIECESUPPORT; A FLOAT ARM MOUNTED ON SAID SUPPORT PIVOTALLY ABOUT A FLOATPIVOT AXIS; A FLOAT ATTACHED TO SAID FLOAT ARM AWAY FROM SAID FLOATPIVOT AXIS; A SWITCH ARM MOUNTED ON SAID SUPPORT PIVOTABLY ABOUT ASWITCH ARM PIVOT AXIS; SAID SWITCH ARM PIVOT AXIS BEING REMOVED FROMSAID FLOAT AXIS; SAID FLOAT PIVOT AXIS BEING SUBSTANTIALLY PARALLEL TOSAID SWITCH ARM PIVOT AXIS; TWO RODS, ONE PIVOTABLY CONNECTED TO THEFLOAT ARM ON ONE SIDE OF THE FLOAT PIVOT AXIS, ONE PIVOTABLY CONNECTEDTO THE FLOAT ARM ON THE OTHER SIDE OF THE FLOAT PIVOT AXIS; BOTH RODSABUTTING ON SAID SWITCH ARM IN A SLIDING PUSHING CONTACT ON THE SAMESIDE OF SAID SWITCH ARM PIVOT AXIS WHEN SAID SWITCH ARM IS IN ITSCIRCUIT MAKING POSITION, A GUIDE MEANS FORMING AN INTEGRAL PART OF SAIDONE-PIECE SUPPORT TO PREVENT LATERAL VIBRATION AND DEFLECTION OF SAIDROD MEANS; SAID GUIDE MEANS BEING A PLATE HAVING A GUIDE HOLE FOR EACHROD; SAID PLATE LOCATED